isoetes lacustris

Isoetes lacustris, the lake quillwort or Merlin's grass, is a boreal quillwort native on both sides of the northern Atlantic Ocean. Synonyms include Isoetes hieroglyphica.

The lake quillwort has many long, narrow leaves from 8–20 cm long and 0.5–2 mm broad, widening to 5 mm broad at the base. There is a sac that produces the spores at the bottom of each leaf base. The plant has a very short stem, called a corm, where all the leaves and roots are attached close together. It does not have traditional ...